Sperm Keeps You Young And 49 Other Sex Facts You'll Be So Glad You Learned

By Zlata Faerman

We always knew that sex ed in middle school didn't teach us everything (or even close to it, let's be honest) — but after reading all these crazy facts, we think that class needs a complete overhaul. From the art of the female orgasm to STIs and condoms, here are 50 sexual truths that will fascinate and entertain you.

How many of these did you actually know?

1. We automatically perceive people who smell good as more attractive.

3. A study found that men feel more emotional pain after a breakup than women do.

4. It's official: This study shows that men and women cannot be just friends.

5. Some people consider sperm to be an anti-aging treatment, as it has a tightening effect on the skin.

6. Sleep-deprived men are more likely to believe women want to have sex with them. This is not a joke.

7. People who are into kinkier sex may be psychologically healthier.

8. Endorphins released during sexual activity create a euphoria similar to opioid drug use.

9. Some people experience the same feeling of arousal when thinking about food as when having sex.

10. After ovulation, a female's egg is fertile for 24 to 48 hours, and a man's sperm can live 48 hours inside the female body. Do the math, and be careful. There have been documented cases of live sperm discovered eight days after sex.

11. Twelve per cent of adults have had sex at work.

12. You can't say happiness without saying penis. (You're welcome.)

13. Only 57 percent of women orgasm while having sex with a partner.

14. The Kama Sutra lists 30 types of kisses. How many have you tried?

15. A study found that good sex triggers the region of the brain associated with falling in love.

16. Men who have sex at least twice a week can almost halve their risk of heart disease, according to a 2010 study.

17. Still have that condom from a while back? Toss it! The average shelf life of a latex condom is about two years.

18. It's a good idea to keep your own condoms, since you don't know how long your partner's been holding on to his. Condoms kept in wallets for over a month are more likely to break.

19. There are five to seven calories in a teaspoon of semen.

20. One orgasm a day may decrease a man's risk for prostate cancer.

21. There are some foods that boost your sex drive, one of them being black raspberries. This phytochemical-rich food enhances both libido and endurance. Oysters are high in zinc, which is vital for testosterone production and healthy sperm. Watermelon contains citrulline amino acid, good for the cardiovascular system and to help relax the blood vessels that increase your sex drive.

22. The average vagina is 3 to 4 inches long but can expand by 200 per cent when sexually aroused.

24. Sex is 10 times more effective than Valium.

24. Shaving your pubic area increases your chances of spreading an STI.

25. Yeah, they're called STIs (sexually transmitted infections) now instead of STDs (sexually transmitted diseases).

26. A woman's butt sticks out 25 per cent more when she is wearing heels. No wonder Jimmy Choo is adored worldwide.

27. In a newer study, one in nine young women has used the morning-after pill after sex.

28. Stay on top of your visits to the gynecologist. Many of the worst STIs you can contract have absolutely no symptoms at all for up to three to five years.

29. Keep it PG and still feel good. The nerve endings in the clitoris extend out to where the pubic hair grows, which is why grinding (dry humping) feels so good.

30. Your pain threshold can increase significantly during arousal.

31. The amygdala, the part of your brain that triggers fear and anxiety, shuts down in women when they have an orgasm.

32. Having an orgasm releases an anti-diuretic hormone, which is why you probably find yourself not able to pee right after sex.

33. You should pee as soon as possible after sex to prevent UTIs (urinary tract infections).

34. A blow job is the No. 1 sexual act desired by straight men.

35. The average cost of a bra-and-panty set is $75. If you're on a budget, skip the seduction, and go straight to the naked.

36. Every year, 11,000 Americans injure themselves when trying out bizarre sexual positions. Don't become a statistic.

37. The largest penis on record is 18.9 inches long. The owner says it has ruined his life.

38. Eighty per cent of women use vibrators to achieve an orgasm by clitoral stimulation rather than inserting it vaginally.

39. It's possible for women to achieve orgasm from breast stimulation alone.

40. According to a 2008 survey of sex therapists, sex is too short when it lasts one two minutes, adequate is three to seven minutes, and desirable is seven to 13. If you're still going at 30 minutes, most people will think it's too long.

41. A new study estimates that 15 percent of women have experienced an orgasm during exercise.

42. Women over 40 years old are more likely to have multiple orgasms than women in their 20s, according to a report.

43. According to a survey of adults aged 20 to 59, women have an average of four sex partners during their lifetimes, and men have an average of seven.

44. Some sexual dysfunction can stem from how a woman feels about the appearance of her genitals. Love your body. All of it.

45. Festival-goers would rather spend time doing drugs, drinking and having sex than watching the concert they paid big money to see.

46. Women with higher testosterone levels might be more interested in masturbation than in having sex with someone else.

47. New moms are ready to have sex sooner than the six-week wait period instructed by their doctor.

48. Nipples are erogenous zones because the sensation of hardened nipples travels to the same part of the brain as do sensations from the vagina, cervix and the clitoris.

49. Almost half of American men have HPV.

50. About 75 percent of men always reach orgasm during sex.

This article was originally published at SheKnows. Reprinted with permission from the author.